Talk:Chronology of the universe

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Outline of Chronology at Odds with Cosmological Standard Model[edit]

The image im Chronology shows Inflation which - while it does explain the fine adjustment problem underlying the flatness of space - is by its nature of taking place before recombinant an unfalsifiable hypothesis and is not part of the standard model. PixelRayn (talk) 11:52, 30 June 2022 (UTC)[reply]

The article, nor the image you mention, does not claim to represent only the Lambda-CDM model, which is not at odds with and can accommodate inflation. As for its falsifiability, some cosmologists (like Roger Penrose) would argue that it very well is falsifiable and may have already been falsified. But until some general consensus among cosmologists is reached, and as inflation is currently a popular explanation for big bang cosmology, I don't see any issues with including it in this article. Especially since the article does mention its standing, or lack thereof, in the various big bang stages. elentir (talk) 12:36, 30 June 2022 (UTC)[reply]

Detecting photons from 13.2+ billion light years away.[edit]

For the Hubble and Webb telescopes to be able to detect radiation from over 13 billion light years away then the dark or ordinary matter that our galaxy is made from must have already existed at or near that distance from the origin of the universe when those early galaxies started forming.

If this is not the case then the universe must have expanded about 13 billion times faster than light else that radiation would already have passed us billions of years ago never to be detectable again. 

What am I missing in my understanding? 86.15.61.16 (talk) 16:08, 13 July 2022 (UTC)[reply]

The universe is expanding, which means that we're not seeing further out but rather the space between us is increasing. The expansion is happening in all directions, so the origin (or centre) of the universe is not one specific point in space, but everywhere in space. See: Expansion of the universe, Hubble's law. Lightbloom (talk) 19:39, 8 September 2023 (UTC)[reply]

Emergence of nucleons may have been earlier than stated[edit]

The following:

"At about one second, neutrinos decouple; these neutrinos form the cosmic neutrino background (CνB). If primordial black holes exist, they are also formed at about one second of cosmic time. Composite subatomic particles emerge—including protons and neutrons—and from about 2 minutes, conditions are suitable for nucleosynthesis"

This implies the first emergence of nucleons was after one second.

Later, the Tabular Summary says that hadronisation will occur at 1e-5 seconds and 150 MeV. This is much earlier than one second; the 150 MeV value is consistent with the article "Color Confinement" which states the Hagedorn temperature corresponds to 130 to 140 MeV.

Spope3 (talk) 05:11, 15 September 2022 (UTC)[reply]

Article issues and classification[edit]

It is practically impossible to tell what is original research and what is not. There are unsourced sentences, paragraphs, and subsections. The article has "citation needed" tags from April 2018, September 2018, September 2020, and January 2023. There is also a March 2021 "section needs additional citations" tag.
The B-class criteria #1 states; The article is suitably referenced, with inline citations. It has reliable sources, and any important or controversial material which is likely to be challenged is cited. According to this the article does not meet the criteria.
There are thirteen entries in the "External links". Three seems to be a normally acceptable number and of course, everyone has their favorite to add for four. The problem is that none is needed for article promotion.
For the sake of completeness and perspective, I recommend that the Tabular Summary be expanded by one column to show the radius of the universe at each state/time period described, rather than simply and unsystematically throwing size/radius information into the general descriptions.
  • ELpoints #3) states: Links in the "External links" section should be kept to a minimum. A lack of external links or a small number of external links is not a reason to add external links.
  • LINKFARM states: There is nothing wrong with adding one or more useful content-relevant links to the external links section of an article; however, excessive lists can dwarf articles and detract from the purpose of Wikipedia. On articles about topics with many fansites, for example, including a link to one major fansite may be appropriate.
  • WP:ELMIN: Minimize the number of links. -- Otr500 (talk) 16:57, 27 February 2023 (UTC)[reply]